document.write( "Question 1135355: A landscaping company needs 120 gallons of 13​% fertilizer to fertilize the shrubs in an office park. They have in stock 20​% fertilizer and 10​% fertilizer. How much of each type should they mix​ together? \n" ); document.write( "
Algebra.Com's Answer #752963 by ikleyn(52797)\"\" \"About 
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document.write( "Let x = the amount of the 20% fertilizer (in gallons) and y = the amount of the 10% fertilizer.\r\n" );
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document.write( "Then you have two equations\r\n" );
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document.write( "         x +     y = 120       gallons  of the mixture                (1)\r\n" );
document.write( "and\r\n" );
document.write( "     0.20x + 0.10y = 0.13*120  gallons  of the pure  fertilizer       (2)\r\n" );
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document.write( "So, your system of equations is THIS\r\n" );
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document.write( "         x +     y = 120         (1)\r\n" );
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document.write( "     0.20x + 0.10y = 0.13*120    (2)\r\n" );
document.write( "         \r\n" );
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document.write( "It can be solved by Substitution or Elimination method, on your choice.\r\n" );
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document.write( "If you solve by Elimination, multiply eq(1) by 0.2 (both sides) and keep eq(2) as is, with no change. You will get\r\n" );
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document.write( "     0.20x + 0.20y = 0.20*120    (1')\r\n" );
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document.write( "     0.20x + 0.10y = 0.13*120    (2)\r\n" );
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document.write( "----------------------------------------- Now subtract eq(2) from eq(1')\r\n" );
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document.write( "                                          The terms \" 0.20x \" will cancel each other, and you will get\r\n" );
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document.write( "             0.20y - 0.10y = 0.20*120 - 0.13*120,   \r\n" );
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document.write( "which gives you\r\n" );
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document.write( "             y = \"%280.20%2A120+-+0.13%2A120%29%2F%280.20+-+0.10%29\" = one click in my Excel = 84.\r\n" );
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document.write( "ANSWER.  84 gallons of the 10% fertilizer and  the rest (120-84) = 36 gallons of the 20% fertilizer.\r\n" );
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document.write( "CHECK.  0.1*84 + 0.2*36 = 15.6 gallons of the pure fertilizer = 0.13*120.   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "It is a standard and typical mixture problem.\r
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\n" ); document.write( "\n" ); document.write( "For introductory lessons covering various types of mixture word problems see\r
\n" ); document.write( "\n" ); document.write( "    - Mixture problems\r
\n" ); document.write( "\n" ); document.write( "    - More Mixture problems\r
\n" ); document.write( "\n" ); document.write( "    - Solving typical word problems on mixtures for solutions \r
\n" ); document.write( "\n" ); document.write( "    - Typical word problems on mixtures from the archive\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "You will find there ALL TYPICAL mixture problems with different methods of solutions,
\n" ); document.write( "explained at different levels of detalization,  from very detailed to very short.\r
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\n" ); document.write( "\n" ); document.write( "Read them and become an expert in solution mixture word problems.\r
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\n" ); document.write( "\n" ); document.write( "Also,  you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook in the section \"Word problems\" under the topic \"Mixture problems\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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